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Letteratura scientifica selezionata sul tema "Succès reproductif"

Autore: Grafiati

Pubblicato: 21 settembre 2023

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Articoli di riviste sul tema "Succès reproductif"

1

Pérusse, Daniel. "Succès social et succès reproductif dans les sociétés modernes : une analyse sociobiologique". Anthropologie et Sociétés 12, n. 3 (10 settembre 2003): 151–74. http://dx.doi.org/10.7202/015043ar.

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Résumé Succès social et succès reproductif dans les sociétés modernes : une analyse sociobiologique Dans cet article, nous présentons l'hypothèse sociobiologique voulant qu'il existe une relation positive entre le succès social et le succès reproductif chez les individus. Cette question se révèle particulièrement significative en ce qu'elle récapitule le rapport entre le comportement culturel et ses déterminants évolutifs. Nous proposons un modèle théorique détaillé de la relation, et nous en vérifions la validité par une revue des recherches pertinentes effectuées au sein des sociétés modernes, où le rapport entre les deux formes de succès apparaft le moins évident.

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Lefebvre, Louis. "L'imitation à l'origine de la culture". Anthropologie et Sociétés 12, n. 3 (10 settembre 2003): 93–107. http://dx.doi.org/10.7202/015040ar.

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Résumé L'imitation à l'origine de la culture Les racines animales de la culture humaine se trouvent dans l'apprentissage social. Cet article décrit une série de travaux récents sur l'imitation et les traditions culturelles chez les oiseaux et les mammifères. Les implications de ces études pour notre compréhension de la culture humaine sont discutées. La théorie coévolutive fournit un scénario plausible des origines de la culture humaine. La question de savoir si des pratiques culturelles particulières contribuent au succès reproductif est plus problématique. Les objections logiques à l'application du concept d'adaptation biologique à la culture sont soulignées.

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Bollmann, Kurt, e Heinz-Ulrich Reyer. "Reproductive Success of Water Pipits in an Alpine Environment". Condor 103, n. 3 (1 agosto 2001): 510–20. http://dx.doi.org/10.1093/condor/103.3.510.

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Abstract To understand the evolution of avian reproductive strategies it is important to assess how differences in reproductive success are related to timing of the breeding season, quality of nesting territories or breeders, or to a combination of these factors. Over three years, we studied the reproductive performance of female Water Pipits (Anthus spinoletta) in a temporally and spatially variable alpine environment. The study area covered two valley slopes that differed in the probability of nest predation, food availability, and climate. Nest predation and harsh weather were the main proximate causes of differences in female reproductive success. Because these two environmental factors were locally unpredictable, individual females could best optimize their seasonal reproductive success by choosing the “right” breeding time. The average number of young fledged per season was inversely related to the date of initial breeding and increased from females with only first attempts, through females with replacement clutches, to females that raised two broods. Hence, the main advantage of early breeding lies in the chance of rearing a second brood after the first has fledged, or of producing a replacement clutch if the first fails due to predation or harsh weather. Éxito Reproductivo de Anthus spinoletta en un Ambiente Alpino Resumen. Para entender la evolución de las estrategias reproductivas de las aves es importante determinar cómo las diferencias en el éxito reproductivo se relacionan con el comienzo de la época reproductiva, la calidad de los territorios de nidificación o los reproductores o con una combinación de estos factores. Durante un período de tres años, estudiamos el desempeño reproductivo de hembras de Anthus spinoletta en un ambiente alpino temporal y espacialmente variable. El sitio de estudio comprendió dos laderas que diferían en la probabilidad de depredación de nidos, disponibilidad de alimento y clima. La depredación de nidos y el clima severo fueron las principales causas proximales de la diferencia del éxito reproductivo de las hembras. Debido a que ambos factores ambientales fueron localmente inpredecibles, cada individuo hembra podía optimizar el éxito de su período reproductivo eligiendo el tiempo “correcto” para reproducirse en la temporada. El número promedio de juveniles por temporada se relacionó inversamente con la fecha del inicio de la reproducción y aumentó desde hembras con sólo un intento de cría, pasando por hembras que reemplazaron sus nidadas, hasta hembras que criaron dos nidadas. Por tanto, la ventaja principal de reproducirse tempranamente en la temporada está dada por la posibilidad de criar una segunda nidada luego de la partida de los primeros juveniles o de producir una nueva nidada si la primera falla debido a depredación o clima severo.

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Porneluzi, Paul A. "Prior Breeding Success Affects Return Rates of Territorial Male Ovenbirds". Condor 105, n. 1 (1 febbraio 2003): 73–79. http://dx.doi.org/10.1093/condor/105.1.73.

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AbstractI examined the hypothesis that male Ovenbirds (Seiurus aurocapillus) make breeding dispersal decisions based on prior breeding experience at a site. I determined the reproductive success of color-banded male Ovenbirds at sites in fragmented and unfragmented landscapes in Missouri from 1992–1995. I documented which individuals returned and I recorded their reproductive success upon return as well as the success of birds new to each plot. I obtained similar results in both landscapes. Males with different histories of reproductive success returned at different rates. Only 2 of 22 males that were paired but failed to raise young returned in the following year, whereas the return rates of unpaired males (41%, n = 37) and males that successfully raised young (54%, n = 57) did not differ significantly (P = 0.19). The patterns were more consistent with the hypothesis that return rates were due to decisions about dispersal rather than difference in survival of individuals in these groups.El Éxito Reproductivo Previo Afecta Índices de Regreso de Machos Territoriales de Seiurus aurocapillusResumen. Examiné la hipótesis de que individuos de Seiurus aurocapillus hacen decisiones de dispersión reproductiva basadas en las experiencias reproductivas previas en un sitio. Determiné el éxito reproductivo de machos con anillos de color en lugares en terrenos fragmentados y no fragmentados de Missouri entre 1992 y 1995. Documenté cuáles individuos regresaron y su éxito reproductivo al regresar, y también el éxito de pájaros nuevos en cada sitio. Obtuve resultados semejantes en ambos paisajes. Los machos con historias de éxito reproductivo diferentes presentaron índices de regreso diferentes. Solamente 2 de 22 machos apareados que no produjeron cría volvieron al año siguiente, mientras que los índices de regreso de machos no apareados (41%, n = 37) y de los machos que produjeron crías exitosamente (54%, n = 57) no difirieron significativamente (P = 0.19). Los patrones concuerdan más con la hipótesis de que los índices de regreso se deberieron a las decisiones de dispersión y no a la diferencia de supervivencia de individuos en estos grupos.

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Kilpatrick, A. Marm, Dennis A. LaPointe, Carter T. Atkinson, Bethany L. Woodworth, Julie K. Lease, Matthew E. Reiter e Kevin Gross. "Effects of Chronic Avian Malaria (Plasmodium Relictum) Infection on Reproductive Success of Hawaii Amakihi (Hemignathus Virens)". Auk 123, n. 3 (1 luglio 2006): 764–74. http://dx.doi.org/10.1093/auk/123.3.764.

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Abstract We studied the effects of chronic avian malaria (Plasmodium relictum) infections on the reproductive success of a native Hawaiian honeycreeper, Hawaii Amakihi (Hemignathus virens). Chronic malaria infections in male and female parents did not significantly reduce reproductive success as measured by clutch size, hatching success, fledging mass, number of nestlings fledged, nesting success (daily survival rate), and minimum fledgling survival. In fact, nesting success of pairs with chronically infected males was significantly higher than those with uninfected males (76% vs. 38%), and offspring that had at least one parent that had survived the acute phase of malaria infection had a significantly greater chance of being resighted the following year (25% vs. 10%). The reproduction and survival of infected birds were sufficient for a per-capita population growth rate >1, which suggests that chronically infected Hawaii Amakihi could support a growing population. Efectos de las Infecciones Crónicas de Malaria Aviaria (Plasmodium relictum) en el Éxito Reproductivo de Hemignathus virens

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Kosciuch, Karl L., Andrew C. Kasner e Keith A. Arnold. "Annual Reproductive Success of Culvert-Dwelling Cliff Swallows in East-Central Texas". Condor 103, n. 4 (1 novembre 2001): 879–85. http://dx.doi.org/10.1093/condor/103.4.879.

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Abstract Most studies describing reproductive biology of an avian species provide some measure of annual reproductive success (ARS), frequently reported per nest or per egg. These measurements do not indicate the success of average females in the population. We report conventional measures of reproductive success along with ARS(b), number of broods successfully reared per female, and ARS(k), number of young successfully reared per female. We calculated ARS for four culvert-dwelling Cliff Swallow (Petrochelidon pyrrhonota) colonies in east-central Texas from 1982 to 1985 (n = 1805 nests) and compared our calculations of ARS with those reported for other regions. We analyzed differences in number of fledglings per female to estimate variation in ARS among years and among culverts. In east-central Texas, ARS differed significantly among years and among culverts. We attributed variation in ARS to predation and abiotic factors. Consistent reporting of ARS would facilitate comparisons among populations or species over multiple scales. Éxito Reproductivo Anual de Petrochelidon pyrrhonota que Forman Colonias en Puentes del Este-Central de Texas Resumen. La mayoría de los estudios que describen la biología reproductiva de especies de aves proveen alguna medida de éxito reproductivo anual (ERA), la cual, se reporta frecuentemente por nido o por huevo. Estas medidas no indican el éxito reproductivo de las hembras promedio de la población. Nosotros reportamos medidas convencionales de éxito reproductivo junto con el ERA(b), número de nidadas exitosamente criadas por hembra y ERA(k), número de juveniles exitosamente criados por hembra. Calculamos el ERA para cuatro colonias de Petrochelidon pyrrhonota que habitan puentes en el este-central de Texas desde 1982 hasta 1985 (n = 1805 nidos) y comparamos nuestros cálculos de ERA con aquellos reportados para otras regiones. Analizamos las diferencias en el número de pichones por hembra para estimar variaciones en el ERA entre años y entre puentes. En el este-central de Texas el ERA varió significativamente entre años y entre puentes. Atribuimos la variación en el ERA a depredación y factores abióticos. El informe consistente de valores de ERA facilitaría la comparación entre poblaciones y especies a través de múltiples escalas.

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Gandini, Patricia, Esteban Frere e P. Dee Boersma. "Status and conservation of Magellanic PenguinsSpheniscus magellanicusin Patagonia, Argentina". Bird Conservation International 6, n. 4 (dicembre 1996): 307–16. http://dx.doi.org/10.1017/s0959270900001787.

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SummaryThere are 36 breeding colonies of Magellanic PenguinsSpheniscus magellanicusalong the coast of mainland Argentina. During the breeding period we counted the number of active nests and estimated the breeding population was approximately 652,000 pairs. Development of coastal areas is diminishing the quality of Magellanic Penguin breeding habitat and reducing penguin reproductive success. Adult mortality rates are increasing because of human activities. Maritime petroleum traffic and petroleum operations are known to cause mortality. Fishing activities cause incidental mortality and may negatively affect penguin foraging and reproductive success. In some areas, offal is increasing gull populations with a corresponding increase in predation on penguin eggs and chicks, thereby lowering reproductive success. These sources of mortality are relatively recent and are human caused. We found three areas where human activities are of particular concern: Península Valdés, Golfo San Jorge and Estrecho de Magallanes. Human impacts on Magellanic Penguin populations could be reduced, benefiting the tourist industry where yearly tens of thousands of people come to the provinces of Chubut and Santa Cruz to visit penguin colonies.Existen 36 colonias de pingüino de MagallanesSpheniscus magellanicusa lo largo de la costa Argentina. La población reproductiva se estimó en 652,000 parejas realizando un conteo de nidos activos durante la estación reproductiva. El desarrollo de las áreas costeras está reduciendo la calidad del hábitat de reproducción y el éxito reproductivo del pingüino de Magallanes. El tráfico de petróleo y las actividades relacionadas son conocidas causas de mortalidad. Las actividades pesqueras están causando mortalidad incidental y pueden estar afectando negativamente el éxito de alimentatión y reproductivo. En algunas áreas la basura está contribuyendo al aumento de la población de gaviotas, incrementándose la predación sobre huevos y pichones de pingüino reduciendo su éxito reproductivo. Estas fuentes de mortalidad son relativamente recientes y provocadas por el hombre. Hemos detectado tres áreas donde la mortalidad relacionada con actividades humanas es preocupante: Península Valdés, Golfo San Jorge y Estrecho de Magallanes. El impacto humano sobre la población de pingüino de Magallanes podría reducirse y beneficiar la industria turística de las provincias de Chubut y Santa Cruz, donde anualmente decenas de miles de personas visitan las colonias reproductivas del pingüino.

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Barve, Sahas, Christina Riehl, Eric L. Walters, Joseph Haydock, Hannah L. Dugdale e Walter D. Koenig. "Lifetime reproductive benefits of cooperative polygamy vary for males and females in the acorn woodpecker ( Melanerpes formicivorus )". Proceedings of the Royal Society B: Biological Sciences 288, n. 1957 (18 agosto 2021): 20210579. http://dx.doi.org/10.1098/rspb.2021.0579.

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Cooperative breeding strategies lead to short-term direct fitness losses when individuals forfeit or share reproduction. The direct fitness benefits of cooperative strategies are often delayed and difficult to quantify, requiring data on lifetime reproduction. Here, we use a longitudinal dataset to examine the lifetime reproductive success of cooperative polygamy in acorn woodpeckers ( Melanerpes formicivorus ), which nest as lone pairs or share reproduction with same-sex cobreeders. We found that males and females produced fewer young per successful nesting attempt when sharing reproduction. However, males nesting in duos and trios had longer reproductive lifespans, more lifetime nesting attempts and higher lifetime reproductive success than those breeding alone. For females, cobreeding in duos increased reproductive lifespan so the lifetime reproductive success of females nesting in duos was comparable to those nesting alone and higher than those nesting in trios. These results suggest that for male duos and trios, reproductive success alone may provide sufficient fitness benefits to explain the presence of cooperative polygamy, and the benefits of cobreeding as a duo in females are higher than previously assumed. Lifetime individual fitness data are crucial to reveal the full costs and benefits of cooperative polygamy.

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Morin, A., M. Rughetti, S. Rioux-Paquette e M. Festa-Bianchet. "Older conservatives: reproduction in female Alpine chamois (Rupicapra rupicapra) is increasingly risk-averse with age". Canadian Journal of Zoology 94, n. 5 (maggio 2016): 311–21. http://dx.doi.org/10.1139/cjz-2015-0153.

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In long-lived mammals, costs of reproduction may vary with age. The terminal investment hypothesis predicts greater reproductive effort as females approach the end of their life expectancy. We monitored 97 individually marked female Alpine chamois (Rupicapra rupicapra (L., 1758)) between 2007 and 2013 to determine how age-specific reproduction affected body mass and subsequent reproductive success. We captured and weighed females between April and August and monitored reproductive success from April to October through mother–kid associations. Reproductive success was strongly age-dependent and peaked at 70% for prime-aged females (4–7 years). Reproductive senescence began at 8 years, earlier than reported by other studies of ungulates. There was no clear evidence of reproductive costs in any age class. Reproductive success was very heterogeneous for old females, suggesting variability in the onset of senescence. Old females were less likely to reproduce in poor years despite being heavier than prime-aged females, suggesting reproductive restraint in late life rather than terminal investment. Female mass remained stable from May to August with no effect of lactation. Our results suggest that chamois reproductive strategy becomes increasingly conservative with age, resulting in no detectable costs of reproduction.

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Dumas, Pascale, e Lucie Maillette. "Rapport des sexes, effort et succès de reproduction chez Rubus chamaemorus, plante herbacée vivace dioïque de distribution subarctique". Canadian Journal of Botany 65, n. 12 (1 dicembre 1987): 2628–39. http://dx.doi.org/10.1139/b87-354.

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Studies published on the reproductive success of dioecious species concentrate on the role of sex ratios and pollinator behaviour. In the case of Rubus chamaemorus L., a circumboreal dioecious species, we hypothesized that flower survival and biomass allocation to reproductive tissues, which are climate dependent, also influence fruit production. Only 0.05% of total biomass is allocated to reproduction, whereas 94% goes to underground organs responsible for vegetative propagation. Many male (28 – 51%) and female flower buds (35 – 54%) and young fruits (24–51%) die prematurely mainly because of the climate; fruit production then becomes independent from initial female flower density. The scarcity of female flowers at most sites (except near open water) limits fruit production. The limited sexual reproduction would allow cloudberry to maintain somatic resources, thereby increasing the longevity of individuals and their chance of encountering the climatic conditions required for reproductive success. Such a strategy is adaptive in a variable climate like that of the subarctic. Furthermore, the reduced importance of sexual reproduction would diminish the need to optimize sex ratios. Other selective pressures (e.g., competition) would then favour male clones in most sites, in spite of the unproductive pollen excess.

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Più fonti

Tesi sul tema "Succès reproductif"

1

Jean, Donald. "L'intégration physiologique chez la chicouté, Rubus chamaemorus, et sa contribution au succès reproductif". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ31738.pdf.

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Muller, Karen. "Influence de la plante hôte sur les performances sexuelles des mâles et conséquences sur le potentiel reproductif des femelles phytophages". Thesis, Dijon, 2016. http://www.theses.fr/2016DIJOS021/document.

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L’abondance des insectes phytophages est déterminée par l’influence de facteurs biotiques et abiotiques qui affectent leurs traits d’histoire de vie. Chez les espèces phytophages à reproduction sur capital, la qualité de la plante hôte sur laquelle les individus effectuent leur développement larvaire est un facteur critique affectant le succès reproducteur des adultes. Curieusement, si l’effet de la plante hôte sur le potentiel reproductif des femelles a été largement décrit, il n’a été que peu étudié sur celui des mâles. Par ailleurs, chez les lépidoptères, lors de l’accouplement, la femelle reçoit du mâle un cadeau nuptial sous la forme d’un spermatophore contenant des spermatozoïdes ainsi que des sécrétions produites par les glandes accessoires. Ces sécrétions constituent des bénéfices directs pour la femelle qui pourra les remobiliser pour augmenter sa fécondité. Mon projet de thèse vise à déterminer l’influence de la plante hôte sur les performances reproductives des mâles et d’en évaluer les conséquences sur le potentiel reproductif des femelles et sur l’évolution des stratégies de choix de partenaire chez un papillon ravageur de la vigne, l’Eudémis (Lobesia botrana). Les expériences menées au cours de ces trois années de thèse révèlent que la nutrition larvaire sur différents cépages de vigne module fortement les réserves énergétiques des mâles, affectant leur potentiel reproductif à travers la taille et le contenu des spermatophores qu’ils transfèrent aux femelles pendant l’accouplement. De plus, l’investissement du mâle dans la production de spermatophores décline au cours d’accouplements successifs, les mâles n’étant capables de produire qu’un seul spermatophore riche en nutriments au cours de leur vie. Ces deux facteurs (nutrition larvaire et expérience sexuelle), qui affectent fortement la qualité reproductive des mâles, ont d’importantes conséquences sur le potentiel reproductif de leur partenaire. En effet, les femelles recevant des spermatophores riches en nutriments et en spermatozoïdes ont plus de descendants que celles recevant des spermatophores de moins bonne qualité. Enfin, les femelles semblent capables de discriminer parmi les mâles en se basant sur des critères reflétant leur qualité reproductive, s’accouplant préférentiellement avec ceux leur procurant le plus de bénéfices directs. Ainsi, les résultats de cette thèse confirment l’importance d’intégrer l’effet mâle quand on s’intéresse à l’évolution des populations de phytophages. De plus, identifier les facteurs écologiques modulant les interactions entre les partenaires sexuels chez les espèces menaçant les cultures est crucial pour pouvoir optimiser les programmes de gestion de ces ravageurs
The abundance of phytophagous insects is determined by numerous interacting biotic and abiotic factors. In capital-breeding phytophagous insects, larval host plant quality is a key determinant of the adult phenotype and the performance of both males and females. Curiously, if the effect of host plant quality on female reproductive success is well-established, little effort has been conducted to determine this effect on male reproductive success. Moreover, in Lepidoptera, males transfer to females a spermatophore containing sperm and accessory gland products rich in nutrients that could be reinvested into female reproduction. The aim of this thesis was to evaluate how male larval nutrition on different host cultivars affects male reproductive traits which could, in turn, influence female reproductive output and mate choice strategies in an important grapevine pest, the European grapevine moth (Lobesia botrana). During these three years, we found that the host cultivar for the larvae strongly influences the energy reserves of male adult moths, affecting ultimately their reproductive potential through the size and content of spermatophores they transfer to females at mating. Moreover, male investment in the spermatophore declines over consecutives matings, suggesting that spermatophores are energetically expensive to produce in this monandrous capital breeding species. Thus ‘male quality’ depends on both the male larval origin and mating history, and females receiving protein-rich spermatophores at mating have an overall greater reproductive output than females mated with poor quality males producing less nutritionally rich spermatophores. Finally, females are able to discriminate among males and mate more with males having high sperm quality (virgin males or males from certain cultivars or geographical origins) to obtain substantial direct benefits.The results of this thesis confirm the importance of considering the “male effect” when trying to understand the evolution of phytophagous populations. Moreover, identifying the ecological conditions that influence the mating success of male and female in crop-pest species may lead to a better management of these crop pests

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Renoirt, Matthias. "Influence de l’habitat sur l’écologie et la physiologie du crapaud épineux (Bufo spinosus)". Electronic Thesis or Diss., La Rochelle, 2022. http://www.theses.fr/2022LAROS041.

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Un grand nombre d’études ont mis en avant les effets négatifs des pressions anthropiques dans le temps et dans l’espace sur la biodiversité. Parmi ces pressions anthropiques, les activités et l’expansion agricole jouent un rôle principal dans la modification des milieux et dans la perte de biodiversité. De fait, la question de la persistance des espèces animales dans ce type de milieux se pose. C’est dans ce contexte que ma thèse s’axe. Afin d’étudier les réponses des organismes à un milieu dégradé et les contraintes du paysage sur différents traits d’histoire de vie et l’écologie, je travaille spécifiquement sur une espèce d’amphibien occupant des milieux allant de fortement conservés à fortement dégradés. Afin de comparer les populations de crapauds épineux (Bufo spinosus) forestières et les populations agricoles, j’utilise un vaste panel de marqueurs pour examiner (1) la structure génétique des populations (marqueurs microsatellites), (2) l’écologie alimentaire (isotopes stables), (3) la qualité individuelle (télomères, morphologie, traits de développement) et son impact sur la reproduction. De ce fait et au cours de cette thèse, j’ai pu mettre en relation de nombreux facteurs associés aux paysages agricoles qui soulèvent de nombreuses questions quant au maintien des populations de crapauds épineux. Ainsi, nous avons pu montrer un effet significatif des fertilisants sur la signature isotopique en δ15N des populations de B.spinosus. Aussi, nous avons pu souligner que l’environnement agricole reste suffisamment perméable au maintien de la diversité génétique. Cependant, nous avons mis en évidence de nombreuses contraintes de ce milieu sur la reproduction des populations d’amphibiens, que ce soit par la faible (voir l’absence) abondance de femelles sur les sites de reproduction, et/ou directement sur le succès reproducteur et la qualité de la progéniture. Ces résultats suggèrent de possibles effets à long terme sur les populations d’amphibiens et nous suggérons d’approfondir les différentes voies de recherche que nous suggérons tout au long de cette thèse afin de mieux comprendre les mécanismes sous-jacents à ces résultats et de trouver des solutions quant à la pérennité des espèces sauvages qui n’ont d’autres choix que de s’adapter
A large number of studies have highlighted the negative effects of anthropogenic pressures intime and space on biodiversity. Among these anthropogenic pressures, agricultural activities and expansion play a major role in the modification of environments and in the loss of biodiversity. Questions whether animal species persist in this type of environment arises. My thesis is based on this context. We aimed at study the responses of organism to a degraded environment and the landscape constraints on life history traits and ecology. My work is focused specifically on an amphibian species persisting in habitat ranging from highly conserved to highly degraded by agricultural activities. In order to compare forest and agricultural populations of model species (Spined toad, Bufo spinosus), I relied on a wide variety of markers to examine (1) population genetic structure (micro-satellite markers), (2) feeding ecology (stable isotope), (3) individual quality (telomeres, morphology, developmental traits) and the impact on reproduction. As a result, I was able to connect many factors associated with agricultural landscapes that raised many questions about the persistence of spined toad populations. We were able to show a significant effect of fertilizers on the δ15N isotopic signature of B.spinosus populations. Moreover, we highlighted that agricultural environment allows genetic diversity between populations. However, using correlative approaches, we pointed out various on strains of this environment on the reproduction of amphibians populations, either through low (or no) abundance of females on breeding sites, and/or directly on reproductive success and offspring quality. These results suggest possible long-term effects on amphibian populations, and we suggest that the various avenues of research we suggested throughout this thesis should be pursued in order to better understand the mechanisms underlying these results and to find solutions for the sustainability of wild species that have no choice but to adapt

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Fortin, Margot. "Influence de la bactérie féminisante Wolbachia sur le comportement de choix du partenaire et la fitness de son hôte Armadillidium vulgare". Thesis, Poitiers, 2016. http://www.theses.fr/2016POIT2325/document.

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Ce travail de thèse vise à mieux comprendre les mécanismes de choix du partenaire chez l'isopode terrestre Armadillidium vulgare. Cette espèce est infectée par la bactérie intracellulaire Wolbachia, connue pour manipuler la sexualité de ses hôtes. Chez Armadillidium vulgare, Wolbachia entraine une féminisation des mâles génétiques, les transformant en femelles fonctionnelles. L'objectif est donc à la fois de comprendre comment les individus choisissent leurs partenaires sexuels, mais également de connaître l'effet de Wolbachia sur ces mécanismes de choix. Afin de répondre à ces questions, une approche comportementale a été utilisée, afin de comparer l'attractivité et le comportement de différents types de femelles. Les résultats montrent que les mâles sont capables de discriminer finement entres des femelles ayant différents traits d'histoire de vie ou différents degrés d'apparentement. Nous montrons également que cette discrimination est corrélée à des changements d'odeur des femelles en fonction de leur état reproducteur et infectieux. Les conséquences de ces choix ont également été étudiées via des expériences de reproduction, et il apparaît que les préférences des mâles sont liées à des bénéfices en termes de succès reproducteur. Quant aux femelles, un suivi sur le long terme de différentes situations de sex-ratio révèle qu'à la fois les mâles et le fait qu'elles soient infectées par Wolbachia diminuent leur fitness, et notamment leur succès reproducteur, allant même jusqu'à modifier leurs préférences sociales
This work investigates mate choice in the terrestrial isopod Armadillidium vulgare. This species is parasitized with intracellular bacteria Wolbachia, which is known to manipulate the sexuality of its hosts. In Armadillidium vulgare, Wolbachia lead to a feminization of genetic males, transforming them into functional females. The aim of this thesis was both to investigate how individuals choose their mates, and to understand the effect of Wolbachia on such choices. In order to answer these questions, we used a behavioural approach in order to compare the attractiveness and the behaviour of different kinds of females. The results indicate that males are able to accurately discriminate females with different life history traits or different degrees of relatedness. We also show that such discrimination from males toward females is correlated to females odour change, according to both their reproductive and infection status. The consequences of male mate choice were studied through reproduction experiment, and it seems that male’s preferences are linked to benefits in terms of reproductive success. Concerning females, a long-term monitoring in different sex-ratio conditions reveals that both males' presence and Wolbachia infections decrease their fitness, in particular their reproductive success, or even modify their social preferences

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Whelan, Shannon. "The Role of Temperature in Timing of Reproduction and Reproductive Success of Gray Jays, Perisoreus canadensis". Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/35507.

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Although early reproduction within a breeding season often leads to higher reproductive success in seasonal environments, it is still not well understood how reproductive success can be influenced by climate both indirectly through the timing of breeding or by directly altering parental behaviour. In this thesis, I investigate the role of ambient temperature in reproductive success through its effects on the timing of reproduction and brooding in a population of gray jays, Perisoreus canadensis. In chapter 2, I test whether (i) female gray jays adjust laying date in response to temperature, (ii) individual or environmental characteristics constrain this plasticity, and (iii) laying date influences reproductive success. Females laid earlier in warmer years than in colder years; females partnered with older males laid earlier than females partnered with younger males at colder temperatures, but not at warmer temperatures. Early layers were more likely to rear at least one nestling and have a dominant juvenile survive the summer. These findings suggest that male experience could advance female laying date at cold temperatures and subsequently increase the probability of a positive nesting outcome. Though cold temperatures appear to limit timing of reproduction in gray jays, previous work in this system suggests that cold temperatures could better preserve perishable winter food stores. Thus, in chapter 3, I test whether temperatures during early offspring development interact with timing of reproduction to influence reproductive performance. Colder ambient temperatures during incubation were associated with larger brood sizes than warmer temperatures among late breeders, but temperature did not influence brood size among early layers, indicating that costs of late breeding may be amplified by temperatures that are unfavourable for food storage. This thesis contributes to our understanding of the environmental factors that determine reproductive performance, both through effects on timing of reproduction and after eggs are laid.

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Bründl, Aisha Colleen. "Investissement parental le long d'un gradient altitudinal chez la mésange bleue (Cyanistes caeruleus)". Thesis, Toulouse 3, 2018. http://www.theses.fr/2018TOU30265/document.

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Dans cette thèse, j'examine la dynamique de l'investissement parental et la fitness chez la mésange bleue eurasienne (Cyanistes caeruleus) dans les Pyrénées françaises, et j'évalue les différences potentielles dues à un gradient altitudinal qui crée une variation de "dureté" environnementale. J'ai utilisé de données observationnelles et expérimentales, recueillies de plus de 500 nids de mésanges bleues. Les conditions de reproduction sont " plus dures " en cas de températures plus froides et d'une élévation croissante. J'ai trouvé que l'altitude croissante conduit à une diminution du succès de l'éclosion. Néanmoins, la taille des couvées et la mortalité des couvées sont comparables à travers le gradient. Je suggère que les décisions initiales en matière de procréation, telles que le moment et la quantité de progéniture, déterminent fortement le succès d'une tentative de reproduction. Ces résultats ont des implications pour notre compréhension du succès de reproduction
In this thesis, I examine parental investment and fitness in the Eurasian blue tit (Cyanistes caeruleus) in the French Pyrenees and assess potential differences due to an altitudinal gradient that creates variation in environmental "harshness". I used observational and experimental data, collected from over 500 blue tit nests. Breeding conditions are "harsher" due to colder temperatures with increasing elevation. I found that increasing altitude leads to decreased hatching success. Nevertheless, clutch size and brood mortality is comparable across the gradient. I suggest that initial reproductive decisions such as timing and amount of offspring produced heavily shape the success of a reproductive attempt. These results have implications for understanding reproductive success

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Lacoume, Sandrine. "Développement et succès reproducteur des mâles parasitoïdes, Dinarmus basalis, suite à des contraintes environnementales". Tours, 2007. http://www.theses.fr/2007TOUR4009.

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Les mâles doivent préserver leur potentiel de fertilisation en dépit de contraintes environnementales. Le but de cette thèse est de déterminer l’influence de la ressource hôte et d’un choc froid sur la fitness d’un mâle hyménoptère parasitoïde Dinarmus basalis. Nos résultats ont montré qu’un choc froid appliqué sur un mâle adulte n’affecte pas son potentiel de reproduction. A l’inverse ce choc appliqué durant le développement entraîne une réduction du nombre d’individus émergents, sans altérer la durée de développement. Un résultat semblable est obtenu lors d’une contrainte alimentaire. Celle-ci affecte également le phénotype des mâles en réduisant leur taille corporelle et celle de leur tractus génital. Dans les deux cas, nous avons constaté une réduction de la quantité de spermatozoïdes. Les mâles ayant subi un stress durant leur développement sont capables de s’accoupler, mais sont désavantagés lors de compétitions entre mâles et lors d’accouplements répétés
Males should protect their sperm stock and fertilization potential. The aim of this thesis is to investigate the effects of different environmental constraints on the reproductive success of males of the hymenoptera parasitoid, Dinarmus basalis. We have chosen a biotic factor (host resource) and an abiotic factor (a cold shock). Our results show that a cold choc on adult males does not affect their reproductive potential. However, a cold shock applied during development reduces males’ emergence but not developmental durations. Similar results are obtained with a dietary constraint applied during male development. This constraint affects also male phenotype by reducing both male and genital tract size. A stress applied during development reduces the quantity of sperm. In single mating, these constraints do not prevent male from mating. However, in repeated mating and male-male competition, constraints applied during development disadvantage males

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Grange, Laura Joanne. "Reproductive success in Antarctic marine invertebrates". Thesis, University of Southampton, 2005. https://eprints.soton.ac.uk/41355/.

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The nearshore Antarctic marine environment is unique, characterised by low but constant temperatures that contrast with an intense peak in productivity. As a result of this stenothermal environment, energy input has a profound ecological effect. These conditions have developed over several millions of years and have resulted in an animal physiology that is highly stenothermal and sometimes closely coupled with the seasonal food supply, e.g. reproductive periodicity and food storage. Therefore, Antarctic marine animals are likely to be amongst the most vulnerable species worldwide to environmental modifications and can be regarded as highly sensitive barometers for change. Reproductive success is a vital characteristic in species survival and evaluation of change in reproductive condition with time key to identifying vulnerable taxa. Characterising reproductive success with time is a major requirement in predicting species response to change and the early stages of species loss. Some invertebrates are highly abundant in shallow water sites around the Antarctic and form conspicuous members of the Antarctic benthos. Three common echinoderms and one nemertean were sampled from sites adjacent to the British Antarctic Survey’s Rothera Research Station, Adelaide Island, on the West Antarctic Peninsula between 1997-2001. Reproductive patterns were determined by histological analyses of gonad tissue. This study provided further evidence for inter-annual variation in Antarctic gametogenic development, which appeared to be driven to some extent by trophic position and reliance on the seasonal phytoplankton bloom. The largest variation in reproductive condition was demonstrated for the detritivorous brittle star, Ophionotus victoriae. The seasonal tempos of this echinoderm have been attributed in part, to the seasonal sedimentation events common in the high Antarctic. The reproductive patterns in the scavenging starfish, Odontaster validus and the predatory nemertean, Parborlasia corrugatus showed less inter-annual variation. The de-coupling of these invertebrates from the intensely seasonal phytoplankton bloom appeared to partially account for the reproductive trends observed. The lack of inter-annual variation in the reproduction of the filter-feeding sea-cucumber, Heterocucumis steineni, was somewhat counterintuitive, although problems with sample processing probably accounted for the majority of this anomaly. Echinoderms were also collected during the Antarctic summer field seasons in 2003 and 2004. A series of fertilisation success studies were undertaken comparing the adaptations in an Antarctic and an equivalent temperate starfish to achieve optimal numbers of fertilised eggs, and elemental analyses were used to estimate the nutritional and energetic condition of the bodily and reproductive tissues in two Antarctic echinoderms. Fertilisation studies indicated that Antarctic invertebrates require 1-2 orders of magnitude more sperm to ensure optimal fertilisation success. These sperm tended to be long-lived and capable of fertilising eggs 24+ hours after release. The study suggested that synchronous spawning, aggregations and specific pre-spawning behaviour are employed to help counter the deleterious effects of sperm limitation. The Antarctic eggs and sperm were also highly sensitive to even small modifications in temperature and salinity, affecting the number of eggs fertilised. Such stenothermy is of particular relevance if the 1-2ºC rise in global temperature, predicted over the next century, is realised. Biochemical composition of body components of two species of Antarctic echinoderm indicated a significant difference in the composition between the male and female gonad, particularly in the Antarctic brittle star Ophionotus victoriae. The ovaries contained a much larger proportion of lipid compared to the testes, and demonstrated a distinct seasonality in composition. Higher levels of lipid were observed in the ovary during the austral winter coincident with a period of reproductive investment and maturing oocytes in the gonad. O. victoriae exhibited lower amounts of lipid in the late austral spring suggesting the removal of mature oocytes from the ovary through spawning. The seasonality in composition and the high levels of lipid and protein measured in the ophiuroid gut tissue, suggested the gut might play a role in providing material and energy for metabolic function and possibly gametogenesis; higher lipid levels were apparent during the period of seasonal phytodetrital flux. The role of the pyloric ceaca in asteroids as a nutrient storage organ was also evident in the high levels of both protein and lipid observed in this bodily component in the star fish, Odontaster validus.

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Pellerin, Maryline. "Utilisation et sélection de l'habitat chez le chevreuil à différentes échelles spatio-temporelles". Poitiers, 2005. http://www.theses.fr/2005POIT2301.

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Tallents, Lucy A. "Determinants of reproductive success in Ethiopian wolves". Thesis, University of Oxford, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.442999.

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Più fonti

Libri sul tema "Succès reproductif"

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Lovejoy, David A., e Dalia Barsyte. Sex, Stress and Reproductive Success. Chichester, UK: John Wiley & Sons, Ltd, 2011. http://dx.doi.org/10.1002/9780470979600.

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Lovejoy, David A. Sex, stress and reproductive success. Chichester, West Sussex, UK: Wiley-Blackwell, 2011.

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1933-, Burger Edward J., Georgetown University. Institute for Health Policy Analysis., United States. Environmental Protection Agency. e Risk Science Institute (Washington, D.C.), a cura di. Sperm measures and reproductive success. New York: A.R. Liss, 1989.

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Carrell, Douglas T., a cura di. Paternal Influences on Human Reproductive Success. Cambridge: Cambridge University Press, 2013. http://dx.doi.org/10.1017/cbo9781139169349.

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Sher, Geoffrey. The journey to IVF success. [United States]: Sher Institute for Reproductive Medicine, 2001.

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Beletsky, Les. Red-winged blackbirds: Decision-making and reproductive success. Chicago: University of Chicago Press, 1996.

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Wallace, Janet Clair. Partitioning variance in reproductive success of female goldeneyes. Ottawa: National Library of Canada = Bibliothèque nationale du Canada, 1993.

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Tarantulas: Their captive husbandry & reproduction : a comprehensive guide to the best use of specific equipment and techniques to achieve husbandry and reproductive success. Nottingham: Practical Python, 1993.

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author, Neufeld Marla B., a cura di. ABA guide to assisted reproduction: Techniques, legal issues, and pathways to success. Chicago, Illinois: American Bar Association, 2016.

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H, Clutton-Brock T., a cura di. Reproductive success: Studies of individual variation in contrasting breeding systems. Chicago: University of Chicago Press, 1988.

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Capitoli di libri sul tema "Succès reproductif"

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Adriaens, Pieter, e Andreas De Block. "Decreased Reproductive Success". In Encyclopedia of Evolutionary Psychological Science, 1–3. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-16999-6_42-1.

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Kraft, Veronica, e W. Jake Jacobs. "Differential Reproductive Success". In Encyclopedia of Evolutionary Psychological Science, 1–2. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-319-16999-6_1392-1.

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Adriaens, Pieter R., e Andreas De Block. "Decreased Reproductive Success". In Encyclopedia of Evolutionary Psychological Science, 1870–73. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-319-19650-3_42.

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Kraft, Veronica, e W. Jake Jacobs. "Differential Reproductive Success". In Encyclopedia of Evolutionary Psychological Science, 2004–5. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-319-19650-3_1392.

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Sear, Rebecca. "Height and Reproductive Success". In Homo Novus – A Human Without Illusions, 127–43. Berlin, Heidelberg: Springer Berlin Heidelberg, 2010. http://dx.doi.org/10.1007/978-3-642-12142-5_10.

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Zerbe, James G. "Status and Reproductive Success". In Encyclopedia of Evolutionary Psychological Science, 1–3. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-319-16999-6_2571-1.

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Stevens, Anthony, e John Price. "Reproductive Success and Failure". In Evolutionary Psychiatry, 159–69. London: Routledge, 2021. http://dx.doi.org/10.4324/9781003209256-19.

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Zerbe, James G. "Status and Reproductive Success". In Encyclopedia of Evolutionary Psychological Science, 7937–39. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-319-19650-3_2571.

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Scott, M. P., e S. M. Williams. "Measuring reproductive success in insects". In Experientia Supplementum, 61–74. Basel: Birkhäuser Basel, 1994. http://dx.doi.org/10.1007/978-3-0348-7527-1_5.

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Vollrath, Fritz. "Growth, Foraging and Reproductive Success". In Ecophysiology of Spiders, 357–70. Berlin, Heidelberg: Springer Berlin Heidelberg, 1987. http://dx.doi.org/10.1007/978-3-642-71552-5_27.

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Atti di convegni sul tema "Succès reproductif"

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Cozari, Tudor. "Ecological-evolutionary ethology of the amphibians: conceptual synthesis of research results at regional and European level". In Xth International Conference of Zoologists. Institute of Zoology, Republic of Moldova, 2021. http://dx.doi.org/10.53937/icz10.2021.51.

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Following long-term investigations of over 50 amphibian populations in the Republic of Moldova and Italy, the ecological and evolutionary peculiarities of reproductive behavior in some species of the orders Caudata and Anura were elucidated. For the first time, at the autecological and synecological level, the evaluation of amphibian nuptial systems - parental input, reproductive success, “r” and “K” reproductive strategies and their role in the evolution of sexual selection and the realization of the reproduction potential as a fundamental mechanism for the survival of amphibian populations in various environmental conditions was emphasized.

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Owens, Patrick D., e A. Galip Ulsoy. "Self-Reproducing Machines: Preventing Degeneracy". In ASME 2006 International Mechanical Engineering Congress and Exposition. ASMEDC, 2006. http://dx.doi.org/10.1115/imece2006-14201.

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Machines produced by humans exhibit insufficient complexity to produce similar machines. As John von Neumann originally postulated, if biological systems are able to successfully reproduce, then there must be some characteristic that we can embed in machines to give them the ability to reproduce. Such a self-reproductive machine, also imbued with the ability to do constructive work, could prove enormously useful to the human race. This paper considers a simple self-reproducing machine, which consists of a 2-DOF, planar robot arm capable of picking up and placing the components of another arm. If the robot places the components within the allowable tolerance, then the original arm has successfully reproduced. An assembly line is constructed, so that a self-reproduction process can proceed along a track. If this process eventually fails because one robot is not capable of assembling another, then the system is said to be degenerate. Otherwise, the system is sustainable. A kinematic model that maps component placement errors from one generation of the robot arm to the next was derived. The system exhibited exponential growth in component placement errors. Thus, this self-reproduction system is degenerate. This system is then augmented to provide error-correction during the assembly process. With the application of error-correction the self-reproduction process is made sustainable. The minimal amount of error-correction required to achieve sustainable self-reproduction was investigated through sensor quantization, and it was shown that the amount of fidelity in the error-correction signal determines the success of the self-reproduction process. This self-reproduction system was also analyzed in the context of Kabamba's Generation Theory, which could predict the results obtained through simulation regarding degeneracy or sustainability.

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Cozari, Tudor. "Etologia ecologico-evolutiva a amfibienilor: sinteza conceptuala a rezultatelor investigatiilor la nivel regional si european". In Impactul antropic asupra calitatii mediului. Institute of Ecology and Geography, Republic of Moldova, 2019. http://dx.doi.org/10.53380/9789975330800.17.

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Following from long investigations of more than 50 populations of amphibians from the Republic of Moldova and Italy were elucidated ecological particularities and evolutionary reproductive behavior of some species of Caudata and Anura Orders. For the first time, on Autecological & Sinecological level, has been made assessment of nuptial systems of amphibians – of parental contribution, reproductive success, „r” & „K” reproductive strategies and their role in sexual selection and evolution the attainment of reproductive potential as a fundamental mechanism of survival of amphibian populations in various ambient conditions.

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Baskorowati, Liliana, Rina Laksmi Hendrati, Nur Hidayati, Mashudi, Mudji Susanto e Dedi Setiadi. "Low Reproduction Success of Calliandra calothyrsus and It’s Implication for Breeding". In 3rd KOBI Congress, International and National Conferences (KOBICINC 2020). Paris, France: Atlantis Press, 2021. http://dx.doi.org/10.2991/absr.k.210621.008.

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Pragasam, Sathishkumar. "Eco Friendly Lighting Options for Offshore Installations and Related Design Challenges". In Abu Dhabi International Petroleum Exhibition & Conference. SPE, 2021. http://dx.doi.org/10.2118/207994-ms.

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Abstract The impact of artificial lighting on birds and animals has been a subject of research for many decades. These studies have established that light pollution from offshore facilities result in disturbing effects on migratory birds and marine animals. It is understood from the various studies that light emanating from offshore structures attract birds at night and disorient them during their migratory flight. As they are distracted from their flight path, they are either found trapped by the light that they keep circling around the installations or make them to take shelter in the installations, ultimately making them miss their migratory journey. This results in reduced winter survival and reduced reproduction success. Many birds are also found to die eventually because of bird strike or by getting themselves incinerated in flares. Congregation of birds in offshore installations also lead to risks related to helicopter landing / take-off. It is also observed that artificial light attracts marine species like turtles and fishes, which result in adverse effects like alteration of feeding habits, impacted circadian rhythm and interference with their reproductive function. From the knowledge of aforementioned disruptive effects of artificial lighting, significant efforts have been made to develop lighting systems for offshore installations that are eco-friendly. Various means of mitigating the undesirable effects of artificial lighting in offshore installations are being tried in the last couple of decades.

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Khussein, Abobakr Mohamed Abbakar. "Mechanotherapeutic approaches to manipulate sperm indices: novel ultrasonic methods for treating asthenospermia and potentials for male contraception". In International Scientific and Practical Conference. TSNS Interaktiv Plus, 2023. http://dx.doi.org/10.21661/r-559828.

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The article deals with the fact that sperm motility is a significant predictor of male fertility potential and is directly linked to fertilization success in both natural and some forms of assisted reproduction.

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Klaus, Elisabeth, Laura Bosco, Corina Maurer, Beatrice Schranz, Franziska Arnold, Alain Jacot e Raphael Arlettaz. "Plant reproductive success in highly fragmented Valais vineyard landscapes: a quasi-experimental approach". In 5th European Congress of Conservation Biology. Jyväskylä: Jyvaskyla University Open Science Centre, 2018. http://dx.doi.org/10.17011/conference/eccb2018/107704.

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Santa-Martinez, Emmanuel. "The influence of distinct pollinators on male and female reproductive success in alfalfa". In 2016 International Congress of Entomology. Entomological Society of America, 2016. http://dx.doi.org/10.1603/ice.2016.114572.

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Barichello, Norman. "The Overwhelming Influence of Ptarmigan Abundance on Gyrfalcon Reproductive Success in the Central Yukon, Canada." In Gyrfalcons and Ptarmigan in a Changing World. The Peregrine Fund, 2011. http://dx.doi.org/10.4080/gpcw.2011.0205.

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Lehman, John T. "Optimal Foraging Theory: Lessons and Application to Adaptive Engineering Systems". In ASME 2008 Dynamic Systems and Control Conference. ASMEDC, 2008. http://dx.doi.org/10.1115/dscc2008-2400.

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In biological systems, optimal strategy is generally defined as optimizing fitness, measured as reproductive value (RV), the expectation of producing surviving offspring from time t onward, given that an organism is in state S(t). Any action can be associated with an expectation of immediate reproductive success. Maximum RV results from the action that maximizes the sum of immediate and future surviving offspring. Adaptive biological behavior is the product of historical experience, heritability, individual variation, and differential fitness among individuals. Foraging tasks are a standard test bed for robot research because of their applicability to many problems. Optimal foraging theory offers explanations and predictions with direct applicability to engineering problems. Much theory development involves optimal solutions based on complete information about the system, but animals do not always conform to predictions of such models. Adaptive approximations to optimality in biological systems offer models for design of engineered systems.

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Rapporti di organizzazioni sul tema "Succès reproductif"

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Heifetz, Yael, e Michael Bender. Success and failure in insect fertilization and reproduction - the role of the female accessory glands. United States Department of Agriculture, dicembre 2006. http://dx.doi.org/10.32747/2006.7695586.bard.

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The research problem. Understanding of insect reproduction has been critical to the design of insect pest control strategies including disruptions of mate-finding, courtship and sperm transfer by male insects. It is well known that males transfer proteins to females during mating that profoundly affect female reproductive physiology, but little is known about the molecular basis of female mating response and no attempts have yet been made to interfere with female post-mating responses that directly bear on the efficacy of fertilization. The female reproductive tract provides a crucial environment for the events of fertilization yet thus far those events and the role of the female tract in influencing them are poorly understood. For this project, we have chosen to focus on the lower reproductive tract because it is the site of two processes critical to reproduction: sperm management (storage, maintenance, and release from storage) and fertilization. E,fforts during this project period centered on the elucidation of mating responses in the female lower reproductive tract The central goals of this project were: 1. To identify mating-responsive genes in the female lower reproductive tract using DNA microarray technology. 2. In parallel, to identify mating-responsive genes in these tissues using proteomic assays (2D gels and LC-MS/MS techniques). 3. To integrate proteomic and genomic analyses of reproductive tract gene expression to identify significant genes for functional analysis. Our main achievements were: 1. Identification of mating-responsive genes in the female lower reproductive tract. We identified 539 mating-responsive genes using genomic and proteomic approaches. This analysis revealed a shift from gene silencing to gene activation soon after mating and a peak in differential gene expression at 6 hours post-mating. In addition, comparison of the two datasets revealed an expression pattern consistent with the model that important reproductive proteins are pre-programmed for synthesis prior to mating. This work was published in Mack et al. (2006). Validation experiments using real-time PCR techniques suggest that microarray assays provide a conservativestimate of the true transcriptional activity in reproductive tissues. 2.lntegration of proteomics and genomics data sets. We compared the expression profiles from DNA microarray data with the proteins identified in our proteomic experiments. Although comparing the two data sets poses analyical challenges, it provides a more complete view of gene expression as well as insights into how specific genes may be regulated. This work was published in Mack et al. (2006). 3. Development of primary reproductive tract cell cultures. We developed primary cell cultures of dispersed reproductive tract cell types and determined conditions for organ culture of the entire reproductive tract. This work will allow us to rapidly screen mating-responsive genes for a variety of reproductive-tract specifi c functions. Scientific and agricultural significance. Together, these studies have defined the genetic response to mating in a part of the female reproductive tract that is critical for successful fertllization and have identified alarge set of mating-responsive genes. This work is the first to combine both genomic and proteomic approaches in determining female mating response in these tissues and has provided important insights into insect reproductive behavior.

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Hatch, Douglas R. Steelhead Kelt Reconditioning and Reproductive Success, 2008 Annul Report. Office of Scientific and Technical Information (OSTI), aprile 2009. http://dx.doi.org/10.2172/962227.

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Shortlidge, Erin. Testing the Ecological and Physiological Factors Influencing Reproductive Success in Mosses. Portland State University Library, gennaio 2000. http://dx.doi.org/10.15760/etd.1950.

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4

Andresen, Claire E., e Patrick J. Gunn. Effects of Extended-release Eprinomectin on Replacement Heifer Performance and Reproductive Success. Ames (Iowa): Iowa State University, gennaio 2018. http://dx.doi.org/10.31274/ans_air-180814-511.

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5

Harrison, F. L., e S. L. Anderson. The effects of chronic radiation on reproductive success of the polychaete worm Neanthes arenaceodentata. Office of Scientific and Technical Information (OSTI), dicembre 1988. http://dx.doi.org/10.2172/6608677.

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6

Miller, Patrick, e Ailsa Hall. Behavioral Ecology of Cetaceans: The Relationship of Body Condition with Behavior and Reproductive Success. Fort Belvoir, VA: Defense Technical Information Center, maggio 2012. http://dx.doi.org/10.21236/ada571811.

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7

Simmons, Mary Ann, Ted M. Poston, Brett L. Tiller, Amanda Stegen, Kristine D. Hand e Jill M. Brandenberger. Canada Geese at the Hanford Site ? Trends in Reproductive Success, Migration Patterns, and Contaminant Concentrations. Office of Scientific and Technical Information (OSTI), maggio 2010. http://dx.doi.org/10.2172/981577.

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8

Andresen, Claire E., e Patrick J. Gunn. Effects of Extended-release Eprinomectin on Cow/calf Performance and Reproductive Success in a Fall-calving Herd. Ames (Iowa): Iowa State University, gennaio 2018. http://dx.doi.org/10.31274/ans_air-180814-549.

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9

Jurkevitch, Edouard, Carol Lauzon, Boaz Yuval e Susan MacCombs. role of nitrogen-fixing bacteria in survival and reproductive success of Ceratitis capitata, the Mediterranean fruit fly. United States Department of Agriculture, settembre 2005. http://dx.doi.org/10.32747/2005.7695863.bard.

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Abstract (sommario):

Objectives: to demonstrate nitrogen fixation in the gut of Ceratitiscapitata, the Mediterranean fruit fly and that fixed nitrogen is important for the fly. Background: Fruit flies (Diptera: Tephritidae) are a highly successful, widespread group of insects causing enormous economic damage in agriculture. They are anautogenous, i.e. the acquisition of nitrogenous compounds by both male and female is essential for the realization of their reproductive potential. Nitrogen, although abundant in the atmosphere, is paradoxically a limiting resource for multicellular organisms. In the Animalia, biological nitrogen fixation has solely been demonstrated in termites. Major achievements and conclusions: We found that all individuals of field-collected medflies harbor large diazotrophicenterobacterial populations that express dinitrogenreductase in the gut. Moreover, nitrogen fixation was demonstrated in isolated guts and in live flies and may significantly contribute to the fly’s nitrogen intake. Specific components of these communities were shown to be transmitted vertically between flies. Moreover, we found that the gut bacterial community changes during the fly’s active season both in composition and complexity. Moreover, strong changes in community structure were also observed between the fly's various developmental stages. An initial analysis using SuPERPCR, a technology enabling the detection of minor populations by selective elimination of the dominant 16S rDNA sequences revealed that Pseudomonasspp. may also be part of the gut community. Implications: The presence of similar bacterial consortia in additional insect orders suggests that nitrogen fixation occurs in vast pools of terrestrial insects. On such a large scale, this phenomenon may have a considerable impact on the nitrogen cycle.

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Hao, Hongjuan, Li Feng, Lifei Dong, Wei Zhang e XiaoLi Zhao. Reproductive outcomes of ectopic pregnancy with conservative and surgical treatment. INPLASY - International Platform of Registered Systematic Review and Meta-analysis Protocols, febbraio 2023. http://dx.doi.org/10.37766/inplasy2023.2.0032.

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Abstract (sommario):

Review question / Objective: The objective of this study was to investigate the natural pregnancy outcomes(IUP,REP) of ectopic pregnancy patients by comparing MTX versus surgery, MTX versus salpingostomy, MTX versus salpingectomy, salpingostomy versus salpingectomy, MTX versus expectant treatment. Condition being studied: Ectopic pregnancy(EP) remains one of the most common gynecological emergencies and a leading cause of maternal death in early pregnancy, Increase infertility and repeat ectopic pregnancy. Surgical treatment is considered the gold standard treatment, but with advances in early diagnosis, such as β -hCG levels and transvaginal ultrasound, EP can be diagnosed in the early stage, and the emergency operation rate and mortality rate of ectopic pregnancy are significantly reduced, and some patients can choose to expectant treatment or medical treatment, such as methotrexate (MTX). Naveed AK et al. suggests that expectant treatment is as safe and effective as MTX in EP patients with stable hemodynamic conditions and decreased or low β -hCG levels. The overall success rate of MTX is reported to be as high as 90% when choosing good indications. There is an increasing attention to reproductive outcomes for EP patients, especially for those who want to have a child, so it is crucial to clarify the impact of each treatment modality on natural pregnancy outcome.

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